Kevin Durant will not play for the US team defending their title at this month's Basketball World Cup due to mental and physical exhaustion.

The high-scoring Oklahoma City Thunder forward's withdrawal follows the loss of the Indiana Pacers' Paul George, who last week suffered a compound fracture of his right leg when he landed badly during a team scrimmage.

"This was an extremely difficult decision as I take great pride in representing our country," Durant, who won gold with the national team at the London Olympics and at the 2010 world championships, said.

"After going through training camp ... I realised I could not fulfil my responsibilities to the team from both a time and energy standpoint. I need to take a step back and take some time away, both mentally and physically in order to prepare for the upcoming NBA season."

USA Basketball chief Jerry Colangelo said Durant reached out to him and head coach Mike Krzyzewski on Thursday to explain how he felt.

"His well being is the most important thing to us and we support him taking the time to get ready for next season," said Colangelo.

"He's been part of the national team program for eight years and a big part of the success we have achieved, and we look forward to him being part of our success in the future as well."

Durant, the NBA's most valuable player, was the biggest draw among the 16 players competing for berths on the 12-man team that will represent the United States in the 24-nation tournament starting August 30 in Spain.

In recent weeks, Kevin Love, Blake Griffin, LaMarcus Aldridge and NBA Finals MVP Kawhi Leonard have removed themselves from the pool of players for various reasons.